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As the story progresses she meets many new people like the time traveler Mikuru Asahina, the alien Yuki Nagato, and the esper Itsuki Koizumi. They become members of the SOS Brigade. They were all sent to monitor and observe Haruhi since she has the ability to destroy the universe and make another one. So their mission is to keep her from getting bored or it will be the end of the universe, so they try many antics to keep her entertained.